clear;
syms x;
f=exp(-x*x);
for i=1:4
   df(i)=diff(f,i); 
   disp(df(i));
end
figure(1);
h=ezplot(df(2),[0,1]);
set(h,'linewidth',2);
set(legend,'FontSize',10,'FontName', 'Times New Roman');
saveas(1,'2_df2.png');
h=ezplot(df(4),[0,1]);
set(h,'linewidth',2);
set(legend,'FontSize',10,'FontName', 'Times New Roman');
saveas(1,'2_df4.png');

